/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.tomcat.websocket.server;

import javax.websocket.Extension;
import javax.websocket.HandshakeResponse;
import javax.websocket.server.HandshakeRequest;
import javax.websocket.server.ServerEndpointConfig;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class DefaultServerEndpointConfigurator
		extends ServerEndpointConfig.Configurator {

	@Override
	public <T> T getEndpointInstance(Class<T> clazz)
			throws InstantiationException {
		try {
			return clazz.newInstance();
		} catch (IllegalAccessException e) {
			InstantiationException ie = new InstantiationException();
			ie.initCause(e);
			throw ie;
		}
	}

	@Override
	public String getNegotiatedSubprotocol(List<String> supported,
	                                       List<String> requested) {

		for (String request : requested) {
			if (supported.contains(request)) {
				return request;
			}
		}
		return "";
	}

	@Override
	public List<Extension> getNegotiatedExtensions(List<Extension> installed,
	                                               List<Extension> requested) {
		Set<String> installedNames = new HashSet<String>();
		for (Extension e : installed) {
			installedNames.add(e.getName());
		}
		List<Extension> result = new ArrayList<Extension>();
		for (Extension request : requested) {
			if (installedNames.contains(request.getName())) {
				result.add(request);
			}
		}
		return result;
	}

	@Override
	public boolean checkOrigin(String originHeaderValue) {
		return true;
	}

	@Override
	public void modifyHandshake(ServerEndpointConfig sec,
	                            HandshakeRequest request, HandshakeResponse response) {
		// NO-OP
	}

}
